The present invention relates to a flat cold cathode fluorescent lamp, and more particularly to a flat cold cathode fluorescent lamp which improves luminance in the vicinity of a spacer.
Generally, a flat cold cathode fluorescent lamp is used as a backlight generator for a large liquid crystal display.
Referring to FIGS. 1, 2 and 3, in a conventional flat cold cathode fluorescent lamp, phosphor layers 1a and 2a are formed on the opposing inner surfaces of parallel front and rear plates 1 and 2, respectively. A side plate 3 is provided on the periphery between front and rear plates 1 and 2 to form a closed discharge space where discharge gas is filled. A pair of electrodes 4 are provided adjacent to side plate 3 in the closed discharge space. A plurality of spacers 5' for supporting front and rear plates 1 and 2 are also provided in the closed discharge space. A phosphor layer 5a' connected to phosphor layer la on front plate 1 is formed on the side of spacer 5'.
In the conventional flat cold cathode fluorescent lamp, to enhance the luminance around spacer 5' supporting front and rear plates 1 and 2, phosphor layer 5a' is formed on spacer 5' to be connected to phosphor layer la formed on front plate 1. During the discharge of electrode 4, phosphor layer 5a' formed on spacer 5' emits light which makes the part of phosphor layer 1a around spacer 5' luminous, thereby preventing the luminance around the spacers from lowering. In a large-sized flat cold fluorescent lamp, however, since the amount of light transmitted from phosphor layer 5a' formed on the side of spacer 5' to phosphor layer 1a around the spacers is small, the luminance in the vicinity of the spacers is degraded to cause the picture to smear.